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I'm currently looking to get a battery system installed at home, but I keep wondering if I should go solar as well.
Here's my thinking:
My elec rates are currently 6.5p/kWh 00:00-05:00 & 28p/kWh outside that.
With a battery system, I can charge at 6.5p, and use that throughtout the day & use minimal electricity during the 28p period. This saves me 22p/kWh for most of my usage (lets call it 20p to account for inefficiencies etc).
I use ~5000-6000kWh/year during my peak period, this means if it was all at the cheaper rate, it's £1000-£1200/year cheaper than I'm paying currently.
I've been quoted ~£7500 for a 8kW, 15kWh system (which admittadly, is probably only just big enough, but is in the right ballpark). This would pay back in 6-8 years & with battery tech etc lasting ~10 years, this seems reasonable.
I'm aiming to go the more DIY battery route & approx half the installation costs, so payback should be even better.
However, with solar, From what I'd seen, I'll be looking at at least a similar amount again, and although it'll be free energy during the day, I'll still have the full rate evenings etc, so compared to battery, I'm saving ~7p/kWh 08:00-16:00 (lets say as an average, will be more during summer, less during winter), but paying 22p/kWh more 16:00-00:00 & 05:00-08:00.
So in my head, I'm thinking battery only is cheaper & saves more than solar only, and if I have them both, I'm only actually saving the 7p/kWh during the day, so I'd have to use ~100MWh of solar to payback a 7k solar install, compared with battery only, and this would take ~20 years on current usage.
Am I missing something here? It just really doesn't seem like solar makes sense, as it's more expensive, and it's got a longer payback period.
If it makes a difference, I also have an EV, but that's always charged overnight at the cheap rate. I don't have a heatpump, but I might do in the future, but it still seems to make more sense at this point to pay a couple £k more to get another battery than several times this for solar.
Here's my thinking:
My elec rates are currently 6.5p/kWh 00:00-05:00 & 28p/kWh outside that.
With a battery system, I can charge at 6.5p, and use that throughtout the day & use minimal electricity during the 28p period. This saves me 22p/kWh for most of my usage (lets call it 20p to account for inefficiencies etc).
I use ~5000-6000kWh/year during my peak period, this means if it was all at the cheaper rate, it's £1000-£1200/year cheaper than I'm paying currently.
I've been quoted ~£7500 for a 8kW, 15kWh system (which admittadly, is probably only just big enough, but is in the right ballpark). This would pay back in 6-8 years & with battery tech etc lasting ~10 years, this seems reasonable.
I'm aiming to go the more DIY battery route & approx half the installation costs, so payback should be even better.
However, with solar, From what I'd seen, I'll be looking at at least a similar amount again, and although it'll be free energy during the day, I'll still have the full rate evenings etc, so compared to battery, I'm saving ~7p/kWh 08:00-16:00 (lets say as an average, will be more during summer, less during winter), but paying 22p/kWh more 16:00-00:00 & 05:00-08:00.
So in my head, I'm thinking battery only is cheaper & saves more than solar only, and if I have them both, I'm only actually saving the 7p/kWh during the day, so I'd have to use ~100MWh of solar to payback a 7k solar install, compared with battery only, and this would take ~20 years on current usage.
Am I missing something here? It just really doesn't seem like solar makes sense, as it's more expensive, and it's got a longer payback period.
If it makes a difference, I also have an EV, but that's always charged overnight at the cheap rate. I don't have a heatpump, but I might do in the future, but it still seems to make more sense at this point to pay a couple £k more to get another battery than several times this for solar.
